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Publication numberUS5018840 A
Publication typeGrant
Application numberUS 07/445,097
Publication dateMay 28, 1991
Filing dateDec 6, 1989
Priority dateJul 31, 1985
Fee statusPaid
Publication number07445097, 445097, US 5018840 A, US 5018840A, US-A-5018840, US5018840 A, US5018840A
InventorsKazufumi Ogawa
Original AssigneeMatsushita Electric Industrial Co., Ltd.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Image display device having a photosetting binder
US 5018840 A
Abstract
Disclosed is a liquid crystal composition which may be used for an image display device. The liquid crystal composition includes a plurality of microcapsules in which liquid crystal is enclosed. The microcapsules are colored in red, green, blue and dispersed in binder. When the liquid crystal composition is used for a liquid crystal display device for image display, it becomes very easy to fabricate the display device since liquid crystal, which is rather difficult to be handled, is enclosed in microcapsules.
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Claims(2)
What I claim is:
1. An image display device which comprises liquid crystal elements which elements are composed of
(a) a plurality of microcapsules in which an electric field responsive nematic, twist nematic, smectic or ferro-inductive liquid crystal is enclosed and the outer surface of which is colored said microcapsules being dispersed in a photosetting binder, or p1 (b) a plurality of microcapsules in which an electric field responsive nematic, twist nematic, smectic or ferro-inductive liquid crystal is enclosed said microcapsules being dispersed in a colored photosetting binder,
said liquid crystal elements being held between two confronting electrodes after being photoset in a pattern.
2. An image display device comprising a plurality of colored liquid crystal picture elements disposed in stripe or mosaic form on a single substrate, the said liquid crystal picture elements being composed of:
(a) a plurality of microcapules in which an electric field responsive nematic, twist nematic, smectic or ferro-inductive liquid crystal is enclosed and the outer surface of which is colored said microcapsules being dispersed in a photosetting binder, or
(b) a plurality of microcapules in which an electric field responsive nematic, twist nematic, smectic or ferro-inductive liquid crystal is enclosed said microcapsules being dispersed in a colored photosetting binder,
said elements being held individually between two confronting electrodes after being photoset in a pattern.
Description

This application is a continuation of now abandoned application Ser. No. 281,890, filed Dec. 8, 1988, which application is a continuation of now abandoned application Ser. No. 083,827, filed Aug. 11, 1987, which application is, in turn, a division of now abandoned application Ser. No. 890,654, filed July 30, 1986.

BACKGROUND OF THE INVENTION

This invention relates to an electric-field responsive liquid crystal composition and an electric-field responsive image display device using the same, and more particularly to a flat display panel using liquid crystal for color display of TV picture, computer image or the like.

The conventional color liquid crystal panel was generally an overlaid combination of liquid crystal which is injected among confronting electrodes arranged in a matrix, and color filters. For example, a TFT (thin film transistor) array having picture element electrodes on a glass substrate, and a composition of common transparent electrodes placed on a plurality of red, blue and green color filters formed on a transparent substrate are preliminarily assembled together by means of spacers, and TN (twist nematic) liquid crystal is injected to compose a panel structure, and by installing polarizing plates at the front and back of this panel, and TFT is operated while irradiating with back light, thereby displaying a color image.

Therefore, the liquid crystal is used as a mere shutter of the light passing through the filter which is an individual color element, and the reliability is sufficient, but the conventional constitution and fabrication method involve the following demerits.

That is, since injection of liquid crystal and fabrication of filter are separate steps, the panel assembling process is very complicated, and the productivity is inferior.

SUMMARY OF THE INVENTION

It is hence a primary object of this invention to eliminate the above-discussed defects of the conventional art, by presenting a liquid crystal composition having a plurality of microcapsules in which liquid crystal is enclosed. The microcapsule is colored and dispersed in a binder, or dispersed in a colored binder.

It is further an object of this invention to enable to integrate the liquid crystal injecting step, color filter fabricating step, and panel assembling step, by using a liquid crystal device which has the above-stated liquid crystal composition structure.

These and other objects of the present invention are accomplished by the invention set forth in the appended claims.

According to the present invention as described herein, the following benefits, among others, are obtained:

(1) Since liquid crystal is injected into microcapsule, handling of liquid crystal is easy.

(2) When this liquid crystal composition is used in an image display device, liquid crystal injection step and filter manufacturing step can be done in one process, so that fabrication may be facilitated.

While the novel features of the invention are set forth with particularity in the appended claims, the invention, both as to organization and content, will be better understood and appreciated, along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a process chart to explain the method of fabricating a liquid crystal composition in one of the embodiments of this invention;

FIG. 2 is an enlarged sectional view showing an example of liquid crystal composition; and

FIGS. 3 and 4 are sectional views of image display device using this liquid crystal composition.

DETAILED DESCRIPTION OF THE INVENTION

A liquid crystal composition in one of the embodiments of this invention and an example of fabricating the same are described while referring to FIGS. 1 and 2.

For example, 9 gram of liquid crystal material (21) of nematic type, twist nematic type, smectric type or ferroinductive type is dropped into 30 gram of 10% aqueous solution of gelatin (22), and is dispersed and emulsified (23) while stirring. Further, 30 gram of 10% aqueous solution of gum arabic (24) is added to be mixed (25). Later, by dropping to add 5 ml of 10% acetic acid (26) and 100 to 140 ml of 40 C. warm water (27), and adding 140 ml of 40 C. water (28) and 10% acetic acid (29), the pH is adjusted to 4 to 4.3 to fabricate a capsule prototype (30). Then cooling to about 5 C. (31), and adding 1 ml of 30% formalin (32) and 10% NaOH water (33), the solution is heated to about 50 C. to harden the capsule (34), thereby microcapsules of 1 to 50 μm are formed, in which capsule a liquid crystal is enclosed.

Next, after dehydrating and drying, the liquid crystal are immersed in red, blue or green dyeing bath (35) to stain the microcapsule surface (36). Further by diffusing into a binder (37) made of photosensitive resin or a heat resistance binder, a liquid crystal composition is prepared (38).

FIG. 2 is an enlarged sectional view showing an example of liquid crystal microcapsule composition, in which numeral 60 denotes a capsule and 61 is liquid crystal which fills up the capsule 60.

Incidentally, the same effect is obtained when dispersing into a precolored binder (40) after dehydrating and drying (3) the microcapsule. As the polymer for preparing microcapsule, it may be also possible to use, aside from gelatin, protein such as casein, vegetable gum, cellulose derivative, condensed polymer, waxy matter, or polysaccharides. As the coloring matter, a pigment may be dispersed in the polymer or binder.

The image display device using the above liquid crystal composition and the method of fabricating the same are explained below. As shown in FIG. 3, the above liquid crystal compositions (colored in red, blue and green) are mounted, in stripe or mosaic form, onto a glass substrate 43 on which TFT (thin film transistor) array 41 and transparent picture element electrode 42 are formed. At this time, if the binder is of photosetting type, the photolithographic technique may be employed, but if not photosensitive, printing or similar method may be employed to mount. Furthermore, in contact with said liquid crystal, a transparent substrate 46 on which a common transparent electrode 45 is formed is mounted by way of an adhesive 47, so that an image display panel may be fabricated.

Finally, when the TFT array 41 is driven while irradiating with back light 50 being held by two polarizing plates 48, 49 on both sides, a picture is displayed in the direction of arrow B. In FIG. 3, meanwhile, numeral 51 denotes a green colored microcapsule liquid crystal composition group, 52 is a blue colored one, and 53 is a red colored one. In this case, naturally, the liquid crystal presents orientation and non-orientation within each capsule. By the way, an embodiment of coloring the binder without coloring the capsule is shown in FIG. 4, in which numeral 54 is a green colored binder, 55 is a blue colored one, and 56 is a red colored one, while 57 denotes a liquid crystal composition group of uncolored transparent capsule.

While specific embodiments of the invention have been illustrated and described herein, it is realized that other modifications and changes will occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all modifications and changes as fall within the true spirit and scope of the invention.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3578844 *Feb 23, 1968May 18, 1971Ncr CoRadiation sensitive display device containing encapsulated cholesteric liquid crystals
US3585381 *Apr 14, 1969Jun 15, 1971Ncr CoEncapsulated cholesteric liquid crystal display device
US3600060 *Feb 23, 1968Aug 17, 1971Ncr CoDisplay device containing minute droplets of cholesteric liquid crystals in a substantially continuous polymeric matrix
US3697297 *Oct 22, 1970Oct 10, 1972Ncr CoGelatin-gum arabic capsules containing cholesteric liquid crystal material and dispersions of the capsules
US3732119 *Nov 5, 1968May 8, 1973Ncr CoTemperature sensitive visual display device
US3872050 *Aug 9, 1973Mar 18, 1975William J BentonPolyurethane liquid crystal dispersion system and devices
US3919110 *Nov 8, 1972Nov 11, 1975Champion Int CorpColored organic synthetic pigments and method for producing same
US4175543 *Mar 23, 1978Nov 27, 1979Liquid Crystal Products, Inc.Venipuncture method
US4556289 *Mar 21, 1983Dec 3, 1985Manchester R & D PartnershipLow birefringence encapsulated liquid crystal and optical shutter using same
US4579423 *Jun 29, 1984Apr 1, 1986Manchester R & D PartnershipEncapsulated liquid crystal and method
US4601967 *Dec 6, 1984Jul 22, 1986Ricoh Company, Ltd.Toner particles having a relatively high specific volume resistivity coating layer
US4610945 *Dec 14, 1984Sep 9, 1986Fuji Photo Film Co., Ltd.Encapsulated toner having improved image-forming characteristics
US4688900 *Sep 17, 1985Aug 25, 1987Kent State UniversityMicrodroplets
JPS5689720A * Title not available
JPS54143093A * Title not available
JPS59214016A * Title not available
Non-Patent Citations
Reference
1Berman et al, "A Method for Constructing Very Large Light-Field Pleochroic Liquid Crystal Displays", Preceeding of SID, vol. 21, No. 2, Apr. 1980.
2 *Berman et al, A Method for Constructing Very Large Light Field Pleochroic Liquid Crystal Displays , Preceeding of SID, vol. 21, No. 2, Apr. 1980.
3Clecak et al, "Display Using Liquid Crystal Dyes", IBM Technical Bulletin, vol. 22, No. 6, Nov. 1979.
4 *Clecak et al, Display Using Liquid Crystal Dyes , IBM Technical Bulletin, vol. 22, No. 6, Nov. 1979.
Referenced by
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US5155607 *Mar 15, 1991Oct 13, 1992Fuji Xerox Co., Ltd.Optical modulation display device and display method using the same
US5274481 *Mar 3, 1992Dec 28, 1993Samsung Electon Devices Co. Ltd.Polymer dispersed liquid crystal device having partitions between different colors formed by etch-printing
US5303073 *Jun 24, 1992Apr 12, 1994Kabushiki Kaisha ToshibaDispersion-type liquid crystal display element with oriented dichroic dye in the support media
US5463482 *Oct 18, 1993Oct 31, 1995Raychem CorporationLiquid crystal composite with droplets of plural chiral nematic materials with different reflection bands
US5473450 *Apr 27, 1993Dec 5, 1995Sharp Kabushiki KaishaLiquid crystal display device with a polymer between liquid crystal regions
US5479278 *Oct 16, 1992Dec 26, 1995Dai Nippon Printing Co., Ltd.Method of making a polymer dispersed liquid crystal by electrodeposition
US5541749 *Apr 15, 1994Jul 30, 1996Semiconductor Energy Laboratory Co., Ltd.Electro-optical device
US5585947 *Mar 24, 1994Dec 17, 1996Raychem CorporationMethod of making liquid crystal composite which has interfacial material disposed between liquid crystal and encapsulating medium
US5724110 *May 22, 1995Mar 3, 1998Sharp Kabushiki KaishaLiquid crystal panel and method for producing the same in which the seal section is formed from a mixture of liquid crystal and resin
US5738804 *Jan 4, 1996Apr 14, 1998Raychem CorporationMethod of making a liquid crystal composite including a dye
US5745198 *Jun 27, 1996Apr 28, 1998Raychem CorporationLight valves
US6108062 *Jan 27, 1998Aug 22, 2000Dai Nippon Printing Co., Ltd.Polymer dispersion-type liquid crystal optical device and method for producing the same
US6259497 *Mar 25, 1992Jul 10, 2001The Secretary Of State For Defence In Her Brittanic Majesty's Government Of The United Kingdom Of Great Britain And Northern IrelandLarge area liquid crystal displays
US6704073 *Mar 12, 2002Mar 9, 2004Eastman Kodak CompanyMethod of coating a polymer-dispersed electro-optical fluid and sheets formed thereby
US20120113363 *Oct 20, 2011May 10, 2012Jae-Ik LimLiquid Crystal Display Devices and Methods of Manufacturing Liquid Crystal Display Devices
EP0709713A2 *Oct 31, 1995May 1, 1996Fujikura Ltd.Electrically controlled color display device and method
WO1995025777A1 *Mar 17, 1995Sep 28, 1995Raychem CorpLiquid crystal composite and method of making
WO1995025778A1 *Mar 22, 1995Sep 28, 1995Raychem CorpMethod of making liquid crystal composite
Classifications
U.S. Classification349/89, 349/86
International ClassificationC09K19/54, G02F1/1335, G02F1/1334
Cooperative ClassificationG02F1/1334, G02F1/133516, C09K19/544
European ClassificationC09K19/54A3, G02F1/1334
Legal Events
DateCodeEventDescription
Nov 1, 2002FPAYFee payment
Year of fee payment: 12
Nov 18, 1998FPAYFee payment
Year of fee payment: 8
Sep 29, 1994FPAYFee payment
Year of fee payment: 4